What are the positive aspects of the death penalty?

Why do people tolerate war more than the death penalty, especially against terrorists?

• These are the argument for death penalty: The death penalty is irreversible, which does not allow for correcting mistakes. (tell that to all war victims) The death penalty does not deter crime. (War encourage more war. If anything good people turn warriors when they're treated as enemies anyway and warriors turn heroes.) The death penalty is expensive to carry out. (So war is cheap?) The  death penalty is cruel.  Alternately, the death penalty allows the offender less time than life imprisonment to feel pain and remorse. (And war is, ah never mind on this) The  death penalty weakens the moral force of government by playing to baser  human instincts and undermining public perception of a humane justice system. (obvious) In the past, the death penalty has often been applied in a discriminatory manner. (I suppose every collateral damage in war has been convicted in jury trial objectively. At least on death penalty we rarely make mistakes and when we do it's still a mistake. In war, we deliberately hit people mainly because they live in a different country, or have different religion, etc. That's ultimate discrimination)

• Answer:

  Throughout history, wars have typically been fought to either a)protect your territory, resources and citizens or b) to secure vital/needed resources. Religious, political, ideological, etc. reasons given for war are typically secondary reasons, used to sell the war to the public. However, even without being sold, many people are prepared to tolerate war in another country if it prevents violence at home. Likewise, a loss of access to a vital resource can result in panic, riots or the destabilization of an entire economy. Again, people are prepared to tolerate war somewhere else to prevent great pain for themselves.